Mediterranean and Black Sea sharks risk extinction

The study has found that shark populations in the Mediterranean and Black Sea risk extinction if current fishing pressure continues. Credit: FAO

A new FAO study has found that shark populations in the Mediterranean and Black Sea have dropped dramatically over the last two centuries and now risk extinction if current fishing pressure continues.

The study finds that sharks in the Mediterranean Sea have declined by more than 97% in number and catch weight over the last 200 years.

In the Black Sea, although information is scarce, catches of the main shark species have also declined to about half of catches in the early 1990s.

"This loss of top predators could hold serious implications for the entire marine ecosystem, greatly affecting food webs throughout this region," says the report.

It found that cartilaginous fish species, such as sharks and rays are by far the most endangered group of marine fish in the Mediterranean and Black sea where 85 species are known to occur. Of 71 species assessed in the Mediterranean Sea in 2007, 30 (42%) were found to be threatened, including 13% critically endangered, 11% endangered and 13% vulnerable. Another 18% were categorised as near-threatened.

Characteristics of certain species including low fecundity, late maturity and slow growth make them more vulnerable and issues such as overfishing, wide use of non-selective fishing practices and habitat degradation, along with accidental catch, have all been cited as causes of the drop in numbers.

Fishing activities targeting sharks are also intensifying due to rapidly increasing demand for shark fins, meat and cartilage.

Recent measures adopted by the European Commission to protect sharks and rays are include the prohibition of ‘finning', the reduction of trawl fishing within three nautical miles off the coast to enhance protection of coastal sharks, and the recommendation that Mediterranean and Black Sea countries invest in scientific research programmes aimed at identifying potential nursery areas and to consider time and area closures to protect juveniles of sharks and rays from fishing activities.

The study, Elasmobranchs of the Mediterranean and Black Sea: Status, Ecology and Biology, can be viewed here.